Retrospective study of scintigraphic and radiological findings in 21 cases of enostosis-like lesions in horses

Records of horses admitted to a veterinary surgery in the UK for lameness investigation during 2000 to 2008 were reviewed. Twenty-one horses were identified with both scintigraphic and radiological evidence of enostosis-like lesions (ELLs), in which 68 individual foci of increased radiopharmaceutical uptake were confirmed in 57 long bones. The presenting lameness was attributed to ELLs in 15 of 21 (71 per cent) horses; the remainder were thought to be incidental findings. Five horses were subjected to a repeat examination, four of which showed the occurrence of new lesions in the same or different limbs. Hindlimbs had significantly more lesions than forelimbs, but there was no difference between the right and left limbs. All 18 horses for which follow-up information was available were treated conservatively and returned to soundness after a variable period of time. Following ELL resolution, thoroughbred horses performed at a similar level to that before investigation and diagnosis.